In the present work, thermal evaporation and sol-gel coating techniques were applied to fabricate nanostructured thin ZnO films. The phase structure and surface morphology of the obtained films were investigated by X-ray diffractometer (XRD) and scanning electron microscope (SEM), respectively. The topography and 2D profile of the thin ZnO films prepared by both techniques were studied by optic...

background: bisphenol a (bpa) is one of the hazardous materials causing disruption of endocrine pathways. due to water contamination by this component from multiple sources and the associated health problems, bpa has been the focus of multiple studies. it has been proved that bpa may cause harm because of its impact on estrogenic receptors in human and other organisms. methods: in this study, t...

in this paper, the possibility of using a new ordered nanoporous carbon as a new fiber in headspace solid phase microextraction (hs-spme) to determine of mononitrotoluenes (mnts) in waste water is demonstrated. the structural order and textural properties of the ordered nanoporous carbon were studied by x ray diffraction (xrd), scanning electron microscopy (sem) images and nitrogen adsorption i...

according to the bronsted definition, any compound which has a hydrogen atom is an acid, since itmay be lost as a proton. a thermodynamical cycle is proposed to calculate absolute pka values forbronsted acids in aqueous solution. the equilibrium of dissociation of a bronsted acid depends onthe interaction of the acid and its conjugate base with solvent molecules. there fore the pka valuedepends...

SiO2-TiO2 mixed oxides have been prepared by sol-gel technique from titanium tetraisopropoxide and tetraethylorthosilicate. The prepared materials were characterized by X-ray diffraction, FT-IR spectroscopy, scanning electron microscopy, nitrogen physisorption and UV-vis diffuse reflectance spectroscopy. The results indicate that compared to pure TiO2, the SiO2-TiO2 mixed oxides show higher the...

A bioreactor refers to any manufactured or engineered device that supports a biologically active environment. These kinds of reactors are designed to treat wastewater treatment. Volumetric mass transfer coefficient and the effect of superficial gas velocity, as the most important operational factor on hydrodynamics, in three-phase airlift reactors are investigated in this study. The experiments...

Sulfonated polyether ether ketone (SPEEK) is categorized in a nonfluorinated aromatic hydrocarbon proton exchange membrane (PEM) group and considered as a suitable substitute for common per-fluorinated membranes, such as Nafion, due to wider operating temperature, less feed gas crossover, and lower cost. Since modeling results in a better understanding of a phenomenon, in this study a dynamic o...

fractional flow analysis confirms the advantages of surfactant alternative gas injection (sag) in enhanced oil recovery, but an adsorption phenomenon that has been affected by several factors, weakens the effectiveness of sag injection. in this study, the effects of sacrificial agent, gas phase, and surfactant concentration on adsorption density on silica mineral were investigated by static and...